How to check result set empty or null in linq????

Question

hey frnds ...

i have a query in linq like this.

var res = from UM in linq.AG_User_Masters

where UM.Login_id == txt_loginname.Text

select UM;

now i have to check that res contain any result or not..

but i do not getting this abjectly...

so pls help...

Thanks....

Jaganathan Bantheswaran · Answer

Hi, The res never be null. The linq query will return the IEnumerable . So you have to check like if(res.Count > 0) { // do something }

Vivek Kumar · Answer

Hi, I have tried all of mentioned approaches but once you try to initiate a method on empty output of LINQ query, it will throw exception. The best way is to check: if(res.AsDataView().ToTable.Rows.Count==0) { //your code goes here } Thanks, Vivek

Jaganathan Bantheswaran · Answer

Hi, As Jignesh Trivedi's reply, Assign it to the property. It should work. Let us know if you have doubts.

Jignesh Trivedi · Answer

hi, here i have some suggetion... use if (res!=null && res.Count() > 0 ) { return 1; } else { return 0; } also try... var grid_data = from AG_User_Master in linq.AG_User_Masters where AG_User_Master.user_name.Contains(@txt_search.Text) select new { Name = AG_User_Master.user_name, Login = AG_User_Master.Login_id, Role = AG_User_Master.Role, password = AG_User_Master.password, mydate = AG_User_Master.c_Date, }; dataGridView1.DataSource = grid_data; hope this will help you.

Mukesh Kumar Tiwari · Answer

if (res.Count() > 0 ) { return 1; } else { return 0; } sir this is working..and thanks for lead me...... and one more problem is there var grid_data = from AG_User_Master in linq.AG_User_Masters where AG_User_Master.user_name.Contains(@txt_search.Text) select new { AG_User_Master.user_name, AG_User_Master.Login_id, AG_User_Master.Role, AG_User_Master.password, AG_User_Master.c_Date, //Error is at this point }; dataGridView1.DataSource = grid_data; Error mes is like this: unable to cat object of type System.DateTIme to type system.string

How to check result set empty or null in linq????

Answers (5)